Egregore
An egregore (Greek egregoros, watcher) is, in esoteric tradition, a collective thought-form generated by a group of people who share intense focus on the same goal — religious community, sports fanbase, political movement, esoteric school. The egregore is said to have "life of its own", reinforcing the behavior of group members.
Modern reading
The concept is similar to sociological notions of collective consciousness (Durkheim) or memes (Dawkins). Sociologically valid; "having life of its own" is metaphor for explanatory purposes.